@@ -3059,10 +3059,15 @@ class KernelSsaGraphBuilder extends ir.Visitor {
       return object;
     }
     if (options.experimentNewRti) {
-      // TODO(sra): For new-rti, construct Rti object. [type] could be `List<T>`
-      // or `JSArray<T>`.
+      // [type] could be `List<T>`, so ensure it is `JSArray<T>`.
+      InterfaceType arrayType =
+          InterfaceType(_commonElements.jsArrayClass, type.typeArguments);
+      HInstruction rti =
+          _typeBuilder.analyzeTypeArgumentNewRti(arrayType, sourceElement);
 
-      // For now, fall through.
+      // TODO(15489): Register at codegen.
+      registry?.registerInstantiation(type);
+      return _callSetRuntimeTypeInfo(rti, object, sourceInformation);
     }
     List<HInstruction> arguments = <HInstruction>[];
     for (DartType argument in type.typeArguments) {
@@ -4046,6 +4051,8 @@ class KernelSsaGraphBuilder extends ir.Visitor {
       _handleJsInterceptorConstant(invocation);
     } else if (name == 'getInterceptor') {
       _handleForeignGetInterceptor(invocation);
+    } else if (name == 'getJSArrayInteropRti') {
+      _handleForeignGetJSArrayInteropRti(invocation);
     } else if (name == 'JS_STRING_CONCAT') {
       _handleJsStringConcat(invocation);
     } else if (name == '_createInvocationMirror') {
@@ -4608,6 +4615,24 @@ class KernelSsaGraphBuilder extends ir.Visitor {
     stack.add(instruction);
   }
 
+  void _handleForeignGetJSArrayInteropRti(ir.StaticInvocation invocation) {
+    if (_unexpectedForeignArguments(invocation,
+            minPositional: 0, maxPositional: 0) ||
+        !options.experimentNewRti) {
+      // Result expected on stack.
+      stack.add(graph.addConstantNull(closedWorld));
+      return;
+    }
+    // TODO(sra): Introduce 'any' type.
+    InterfaceType interopType =
+        InterfaceType(_commonElements.jsArrayClass, [DynamicType()]);
+    SourceInformation sourceInformation =
+        _sourceInformationBuilder.buildCall(invocation, invocation);
+    HInstruction rti = HLoadType(interopType, _abstractValueDomain.dynamicType)
+      ..sourceInformation = sourceInformation;
+    push(rti);
+  }
+
   void _handleForeignJs(ir.StaticInvocation invocation) {
     if (_unexpectedForeignArguments(invocation,
         minPositional: 2, maxPositional: null, typeArgumentCount: 1)) {
 
@@ -207,6 +207,11 @@ external JS_INTERCEPTOR_CONSTANT(Type type);
 /// Calls are replaced with the [HInterceptor] SSA instruction.
 external getInterceptor(object);
 
+/// Returns the Rti object for the type for JavaScript arrays via JS-interop.
+///
+/// Calls are replaced with a [HLoadType] SSA instruction.
+external Object getJSArrayInteropRti();
+
 /// Returns the object corresponding to Namer.staticStateHolder.
 external JS_GET_STATIC_STATE();
 
 
@@ -8,6 +8,7 @@ library rti;
 import 'dart:_foreign_helper'
     show
         getInterceptor,
+        getJSArrayInteropRti,
         JS,
         JS_BUILTIN,
         JS_EMBEDDED_GLOBAL,
@@ -271,8 +272,7 @@ Rti instanceType(object) {
     // FWIW, the legacy rti has this problem too. Perhaps JSArrays should use a
     // program-local `symbol` for the type field.
     if (rti != null) return _castToRti(rti);
-    // TODO(sra): Use JS_GET_NAME to access the recipe.
-    throw UnimplementedError('return JSArray<any>');
+    return _castToRti(getJSArrayInteropRti());
   }
 
   var interceptor = getInterceptor(object);
 
@@ -0,0 +1,15 @@
+// Copyright (c) 2019, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+//
+// dart2jsOptions=--experiment-new-rti --no-minify
+
+import "package:expect/expect.dart";
+import "dart:_foreign_helper" show JS;
+
+main() {
+  Expect.equals('JSArray<int>', <int>[].runtimeType.toString());
+
+  // TODO(35084): An 'any' type would make JS-interop easier to use.
+  Expect.equals('JSArray<dynamic>', JS('', '[]').runtimeType.toString());
+}